Hi, Sandra asked me to have a look at this thread and see if I could offer anything extra. I think everyone has done a great job.
All the addresses that have been listed throughout the years are now part of greater Toronto, Ontario.
77 Gilmour Ave, High Park
314 Milverton Blvd, Greenwood
are both part of Toronto
388 Renforth Dr is in Etobicoke which is part of greater Toronto.
The voters lists for 1963/65/68 list Claude and Neta and I think this is the father and not Cecil. Cecil would only be ages 56-61 in that time frame and I don't think he would likely be retired especially living in Toronto. Claude would be 79-83 in that same time frame. The last address given is the one in Etobicoke.
http://pages of the past.ca
The Toronto Star - Pages of the Past
it is a pay site but you can subscribe for as little as 1 hour. If you decide to use the site make sure to read the How to Search and FAQ's before you start as there are good research tips given. I would look for a death for Cecil Doughty in the years between 1957 and 1963 as he isn't listed on the voter's list as Cecil. I would look for a death for Claude in the years after the 1968 voters list.
I went to the on line directory to see if there are listings for Doughty and there are 16 for Toronto and 6 are in the Etobicoke area. Depending on how far you want to take your search, you could always send off a couple of letters by mail. Sometimes you get lucky and contact another person who is interested in genealogy.
There is also a C. Doughty with the same forename as the father who is mayor of Huntsville, Ontario. Huntsville is north of Toronto and I never rule anything out.
I will keep looking and will post if I find anything that I think you can use.
Val